Hydraulic jack and brake arrangement for vertical generators and the like



J y 18, 1944. E. MAINWARING 2,354,031

CK AND BRAKE ANGEMENT FOR HYDRAULIC VERTICAL GENERATORS THE L- OriginalFiled Oct. 194

l WWW I IhventoT:

Waltev- E. Mainwar'mg,

His Attorney.

Patented July 18, 1944 HYDRAULIC JACK-AND BRAKE- ARRANGE- M-ENT roeVERTICAL GENERATORS AND THE LIKE Walter E.- Mairiwa'r-lng, Schenectady.N. Y., as- "signor .t'o'Genera'l Electric Company, .a corporaion of NewYork Original application October 31.1942, Serial No.

Divided and this application September 15, 1943, Serial No. 502,538

2 Claims. (Cl. 171.252)

I This is a division of my application, Serial No. 464,128, filed onOctober 31, 1942, and relating to hydraulic jack and brake arrangementsfor vertical generators and the like. Upon shutdown of vertical electricgenerators, such as are used for example in hydro-electric powerstations, it is often desirable to bring the generator quickly from fullspeed to standstill and also to relieve the pressure of the generatorWeight on the thrust bearing While the generator is out of operation.This has been accomplished heretofore by the provision of brake means toslowdown the generator and jack supporting means for re-" lieving thepressure on thrust bearings during standstill.

The object of my invention is to provide an ii. proved construction ofhydraulic jack and brake arrangements'ior vertical generators the likewhich is both rugged in construction and requires comparatively littlespace.

For consideration of what I believe to be novel my invention, attentionis directed to the following description and the claims appended theretoin connection with the accompanying drawing.

In the drawing Fig. 1 illustrates a sectional view of a hydraulic jackarrangement embodying my invention; Figs. 2 and 3 show front views ofthe arrangement of Fig. 1 in two different operating positions; and Fig.4 shows a vertical generator arrangement according to my invention.

A hydraulic jack and brake arrangement for vertical electric generatorsand the like as illustrated in Fig. 4 comprises a generator I having arotor 2 and a stator 3. The rotor is rotatably held on a foundation orsupporting structure 4. In order to slow down the rotor and bring it toa quick standstill a plurality of jack and brake arrangements 5, 6 areprovided, each arrangement being held on the supporting structure 4 andhaving an element cooperatively associated with a ring or like brakemember 1 securely fastened to and forming part of the rotor 2. Duringnormal operation of the rotor the jack and brake arrangements 5, 6 forma clearance 8 with the adjacent brake surface of the ring 1. Uponshutdown the jack and brake arrangements 5, 6 are raised frictionally toengage the ring 1 and upon standstill to support the rotor 2.

Each arrangement 6 as shown in Figs. 1 to 3 comprises a hydrauliccylinder In with a bottom H fused to a base l2 by a weld I3. A conduit[4 projects through an opening in the base l2 and is secured to achannel I5 in the cylinder wall for conducting fluid under presire,suchas air or oil, to the cylinder. A plunger 01" piston 56 is slidablydisposed within the cylindrical chamber formed by the cylinder Ill. Thepiston to has a central bore H and the lower end of the piston forms acentral cylindrical extension or projection H3. The upper end of thebore l"! is sealed by means of a plug 19. A stud 2'5} screwed into anopening of the bottom I l projects centrally into the bore ii and atitsupper endcarr'ies a nut 2| forming a seat for'the upper end of a helicalspring 22 surrounding the stub fiii'arizd having a lower end bearingagainst a shoulder 23 formed at the lower end of the extension 58. Thespring 22 is under compression biases the plunger IE into its lowerendposition in which it engages the bottom H of the cylinder (Fig. 1).Packing means are provided to reduce'leakage of operating mediumalong'the clearance between the plunger and the wall of the cylinder.This packing means includes a sealing ring 24 having a cylindricalportion engaging the wall of the cylinder IF] and biased radiallyoutward towards the wall by means of a spring 25 held in a retainer 26,which latter together with a disk portion of the ring 24 is secured tothe lower face of the plunger l6 by a plurality of bolts 21. The upperend of the plunger [6 in the present example is secured to a platform orfriction block plate 28 by a plurality of bolts 29. The platform 28carries a shoe in the form of a flat friction block or disk 30 made ofsuitable brake material. The platform and shoe are cooperativelyassociated with an object such as a brake ring 1 to be raised or to beengaged by the block 30 to reduce rotary movement thereof.

During operation, fluid under pressure is supplied to the conduit [4through the lower end of the cylinder II] to efiect upward movement ofthe piston I6. When the piston l6 has been raised to a desired positionit may be held in such position by the provision of means mechanicallylocking Or holding the piston and platform in position. This meansaccording to my invention is in the form of two cylindrical cams 32 and33 having adjacent like cam surfaces 34 and 35 respectively andconcentrically surrounding the cylinder Ill. The lower cam 32 is looselyheld on the base l2 and rotatable about the cylinder Ill whereas theupper cam 33 is secured to the platform 28 by a weld 3B. The upper cam33 has an axial slot 31. A guide pin 38 secured to the cylinder [0projects through the slot 31 and prevents rotational movement of theplunger and the cam 33, which latter is secured to the plunger throughthe intermediary of the platform. The lower cam 32 has a radialprojection or attachment 39 with a bore or opening 40 for receiving arod or like tool to turn the lower cam abut the axis of the cylinder inorder to bring the cam surface 34 of the lower cam into engagement withthe cam surface 35 of the upper cam.

Fig. 2 shows the arrangement in raised position, the cam surfaces 34, 35being axially spaced. After the plunger IS with the platform 28 has thusbeen raised the lower rotatable cam 32 may be turned or rotated untilthe cam surfaces 34, 35 engage each other again. The arrangement isshown in such position in Fig. 3. Thereupon the hydraulic fluid underpressure in the cylinder chamber may be relieved. The platform then isbeing held in elevated position by the cams 34, 35 which togetherconstitute a means for supporting the platform 28 in any raisedposition. The cam surfaces 34, 35 have a small pitch. Therefore, withthe platform or the shoe 30 supporting a heavy object, such as part of alarge hydro-electric generator, the jack could not be loweredmechanically by merely turning the lower cam. In order to lower the jackit is necessary first to admit fluid under pressure to the cylinderchamber in order to raise slightly the upper cam from the lower cam.Thereupon the lower cam may be moved from the position in Fig. 3 intothat of Fig. 2 so that upon release of the fluid pressure the piston l6may move downward into engagement with the bottom II. This downwardmovement is partly efiected by the biasing action of the spring 22.

Thus, with my invention I have accomplished an improved construction ofhydraulic jack arrangements used in combination with vertically disposedelectric generators to bring the rotors thereof to a quick standstillupon shutdown and to hold the rotors in vertically raised position uponrelease of the fluid pressure from the jacks. Upon restarting of therotor it is desirable first to apply fluid pressure to the thrustbearings before the jacks are lowered to permit rotation of the rotor.The jack arrangements reduce considerably the wear of the thrustbearings because they facilitate the formation of a lubricating film onthe thrust bearings while the rotor is standing still.

Having described the method of operation of my invention, together withthe apparatus which I now consider to represent the best embodimentthereof, I desire to have it understood that the apparatus shown is onlyillustrative and that the invention may be carried out by other means.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. Hydraulic jack and brake arrangement for vertical generators and thelike comprising in combination a generator support, a rotor having abrake ring rotatably held on the support, and a plurality of jack andbrake arrangements each being held on the support and having a platformfor engaging the ring, and adjustable cam means for holding the platformin raised position.

2. The combination with a vertical generator having a support, a rotorheld on the support, a brake ring secured to one end of the rotor andfacing the support, and means for slowing down the rotor upon shutdownand holding the rotor in raised position during standstill, said meanscomprising a plurality of hydraulic jack and brake arrangements, eacharrangement including a hydraulic cylinder with a piston movablydisposed in the cylinder, a platform with a friction plate secured tothe piston and facing the ring and two cylindrical cams surrounding thecylinder for holding the platform in raised position.

WALTER E. MAINWARING.

